The present invention relates to foliage trimmers designed for cutting the leaves and branches of asymmetrically convex plants, bushes, shrubs, hedges and the like. Trimming asymmetrically convex shrubs, or the like, manually to a desired shape is very arduous and time consuming operation.
There have been attempts in the past to invent a device to cut convex shapes. Examples of such foliage trimming devices are shown in U.S. Pat. No. 3,487,614, invented by E. Uhor; and U.S. Pat. No. 3,913,304, invented by Paul Jodoin; and U.S. Pat. No. 4,970,791, invented by Florentino S. Vergara; and U.S. Pat. No. 6,151,876, invented by William Van Der Burg; and U.S. Pat. Application No. US 2004/0103631 A1, invented by Jan Pontianus Ezendam and Nicodemus Assisius Ezendam. Unfortunately all these inventions are designed to cut symmetrically convex shapes, thus they are useless in everyday gardens that are made up of asymmetrically convex bushes and furthermore the gardens are not created to accommodate the machinery associated with these trimmers.
Therefore landscapers and others still use conventional linear trimmers that cut in a flat linear plane to trim asymmetrically convex shrubs and the like. Conventional linear foliage trimmers comprise of two straight flat blades situated in facial engagement, with overlapped teeth protruding along their registering edges. A motor means is arranged at one end of the blade assembly to move one of the blades reciprocally or both blades counter reciprocally so the registering teeth slide across one another to cut the foliage projecting through the spaces between the teeth.
In order to cut asymmetrically convex shapes, it is necessary to periodically adjust the angle between the conventional linear trimmer blade assembly and the foliage surface. And multiple passes have to be made to create an asymmetrically convex contour. In many cases the conventional linear trimmer cuts into the foliage contour or creates a flat spot, thus requiring removal of more foliage than is desired. The final condition of the foliage is often not what was initially intended.